sctp: Hold sock lock while iterating over address list

sctp: Hold sock lock while iterating over address list

[ Upstream commit f1fc201148c7e684c10a72b6a3375597f28d1ef6 ]

Move address list traversal in inet_assoc_attr_size() under the sock
lock to avoid holding the RCU read lock.

Suggested-by: Xin Long <lucien.xin@gmail.com>
Fixes: 8f840e47f190 ("sctp: add the sctp_diag.c file")
Signed-off-by: Stefan Wiehler <stefan.wiehler@nokia.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20251028161506.3294376-4-stefan.wiehler@nokia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>